Results 121 to 130 of about 914 (138)

The new gravimetric quasigeoid model KTH08 over Sweden

Journal of Applied Geodesy, 2009
The least squares modification of Stokes formula has been developed in a series of papers published in Journal of Geodesy between 1984 and 2008.
Jonas Ågren, Lars E. Sjöberg, Ramin Kiamehr   +2 more
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The European Gravimetric Quasigeoid EGG96

1997
Within the frame of the European Geoid Project of the International Association of Geodesy (IAG) a significantly improved geoid/quasigeoid model for Europe and surrounding areas was computed at the Institut fur Erdmessung (IfE). For the new solution high resolution gravity and terrain data were combined with a global geopotential model in an optimal ...
Heiner Denker, Dirk Behrend, Wolfgang Torge   +2 more
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Improving the Quasigeoid Model in Colombia

2002
In 1998, the Colombian gravimetric geoid model GEOCOL98 was determined using the remove/restore technique. The local component was computed from Free Air anomalies processed by Stokes’ formula, and the global component was calculated from the EGM96 geopotential model.
W. Martínez, L. Sánchez
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Separation Between Geoid And Quasigeoid In Romania

Proceedings, 2017
In the calculation of the Earth's shape the mass distribution under the ellipsoid is assumed to be homogeneous. A local excess of mass within the ellipsoid will deviate from the local gravity. As a result of the uneven distribution and heterogeneity of the Earth's internal mass, the geoid is a corrugated equipotential surface.
N.-S. Asimopolos, L. Asimopolos
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Explicit formula for the geoid-quasigeoid separation

Studia Geophysica et Geodaetica, 2006
The explicit formula for the geoid-to-quasigeoid correction is derived in this paper. On comparing the geoidal height and height anomaly, this correction is found to be a function of the mean value of gravity disturbance along the plumbline within the topography.
Tenzer R, Novak P, Moore P, Kuhn M, Vanicek P   +4 more
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Quasigeoids for the Territory of the Czech Republic

Studia Geophysica et Geodaetica, 2004
Several quasigeoid models for the Czech Republic have been developed for different purposes since mid-seventies using different data sources: gravimetric, astronomical and GPS/levelling observations, as well as data gained from the territories of neighbouring countries.
J. Kostelecký, J. Kostelecký, I. Pešek, J. Šimek, O. Švábenský, J. Weigel, A. Zeman   +6 more
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On the geoid–quasigeoid separation in mountain areas

Journal of Geodesy, 2009
The separation between the reference surfaces for orthometric heights and normal heights—the geoid and the quasigeoid—is typically in the order of a few decimeters but can reach nearly 3 m in extreme cases. The knowledge of the geoid–quasigeoid separation with centimeter accuracy or better, is essential for the realization of national and international
Jakob Flury, Reiner Rummel
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Quasigeoid evaluation with improved levelled height data for Norway

Journal of Geodesy, 2007
GPS-levelling points are widely used to control gravimetric geoid or quasigeoid models. Direct comparison is often interpreted to reveal the accuracy of the gravimetric model, using GPS-levelling as a reference. However, both GPS and levelled heights contain errors, and in order to achieve a centimeter-accuracy geoid, these should be investigated.
D. I. Lysaker, O. C. D. Omang, B. R. Pettersen, D. Solheim   +3 more
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Quasigeoid and deflection determinations by astrogravimetric methods

Bulletin Géodésique, 1987
The main objective of the present work is to present methods to obtain detailed surveys of the shape of the quasigeoid and of deflections of the vertical from the point of view of three-dimensional constituting and rigorous computing of the astrogeodetic network.
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METHOD FOR CALCULATING GRAVITY ANOMALIES RELATIVE TO A QUASIGEOID

Geology and mineral resources of Siberia, 2022
A method for calculating gravity anomalies relative to a quasigeoid is described. The following formulas are given: reduction of values of the normal gravity from the ellipsoid surface to the quasigeoid surface; calculation of the conditional density of rocks of the Bouger plate; calculation of gravity anomalies relative to the quasigeoid.
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